US5286684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aluminum oxide-based sintered object and process for producing the same
Assignee: Niterra Co Ltd
•
Filing: 1993-02-10
•
Granted: 1994-02-15
•
Expires: 2013-02-10
Abstract
Abstract An aluminum oxide-based sintered object having excellent abrasion resistance includes α-aluminum oxide, a silicon compound and a tungsten compound, wherein the silicon compound and the tungsten compound are present in amounts based on starting amounts of SiC and W metal of from 5 to 40 mole % and from 0.5 to 25 mole %, respectively, based on the sintered object overall, with a W/SiC molar ratio of 4 or less, and in which particles of at least one of tungsten carbide and tungsten silicide having an average particle diameter of 0.5 μm or less are dispersed as a crystalline phase.
Inventors
- 👤 Jun Otsuka
- 👤 Satoshi Iio
- 👤 Yo Tajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:31
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/117; C04B35/622; C04B35/64; C04B35/645; C04B35/6455
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
105 words
An aluminum oxide-based sintered object having excellent abrasion resistance which comprises α-aluminum oxide, a silicon compound and a tungsten compound, wherein the silicon compound and the tungsten compound are present in amounts based on starting amounts of SiC and W metal of from about 5 to about 40 mole % and from about 0.5 to about 25 mole %, respectively, based on the sintered object overall, with a W/SiC molar ratio of 4 or less, and in which particles of at least one of tungsten carbide and tungsten silicide having an average particle diameter of 0.5 μm or less are dispersed as a crystalline phase.
Claim 2
Dependent Claim
105 words
An aluminum oxide-based sintered object having excellent abrasion resistance which comprises α-aluminum oxide, a silicon compound and a tungsten compound, wherein the silicon compound and the tungsten compound are present in amounts based on starting amounts of SiC and W metal of from about 5 to about 40 mole % and from about 0.5 to about 25 mole %, respectively, based on the sintered object overall, with a W/SiC molar ratio of 4 or less, and in which particles of at least one of tungsten carbide and tungsten silicide having an average particle diameter of 0.5 μm or less are dispersed as a crystalline phase.
Claim 3
Dependent Claim
18 words
An aluminum oxide-based sintered object as in claim 1, wherein a silicon-containing glass is present at grain boundaries.
Claim 4
Dependent Claim
35 words
An aluminum oxide-based sintered object as in claim 1, wherein the amount of silicon carbide is 7 to 40 mole % as based on SiC and the molar ratio of W/SiC is 2 or less.
Claim 5
Dependent Claim
25 words
An aluminum oxide-based sintered object as in claim 3, wherein the amount of silicon carbide is 10 to 40 mole % as based on SiC.
Claim 6
Dependent Claim
128 words
A process for producing an aluminum oxide-based sintered object which comprises (1) mixing powders of silicon carbide, SiC, in an amount of from about 5 to about 40 mole %, tungsten, W, in an amount of from about 0.5 to about 25 mole %, and an α-Al 2 O 3 source constituting the remainder, each of the amounts of SiC and W being based on the sum of the SiC amount, the W amount, and the α-Al 2 O 3 source amount determined in terms of α-Al 2 O 3 , and the SiC and W being present in a W/SiC molar ratio of 4 or less, and (2) then sintering the mixture in a non-oxidizing atmosphere at a temperature of from about 1,500° to about 1,900° C.
Claim 7
Dependent Claim
128 words
A process for producing an aluminum oxide-based sintered object which comprises (1) mixing powders of silicon carbide, SiC, in an amount of from about 5 to about 40 mole %, tungsten, W, in an amount of from about 0.5 to about 25 mole %, and an α-Al 2 O 3 source constituting the remainder, each of the amounts of SiC and W being based on the sum of the SiC amount, the W amount, and the α-Al 2 O 3 source amount determined in terms of α-Al 2 O 3 , and the SiC and W being present in a W/SiC molar ratio of 4 or less, and (2) then sintering the mixture in a non-oxidizing atmosphere at a temperature of from about 1,500° to about 1,900° C.
Claim 8
Dependent Claim
32 words
A process for producing an aluminum oxide-based sintered object as in claim 5, wherein the process further comprises subjecting the sinter resulting from the sintering step to a hot isostatic pressure treatment.
Claim 9
Dependent Claim
39 words
A process for producing an aluminum oxide-based sintered object as in claim 5, wherein the amount of silicon carbide is 7 to 40 mole % as based on SiC and the molar ratio of W/SiC is 2 or less.
Claim 10
Dependent Claim
29 words
A process for producing an aluminum oxide-based sintered object as in claim 7, wherein the amount of silicon carbide is 10 to 40 mole % as based on SiC.
References Cited (Backward Citations)
US4069060A
Cited
JPS5252910A
Cited
JPS5624704A
Cited
JPS57205368A
Cited
JPS6259567A
Cited
JPS62153159A
Cited
JPS6317789A
Cited
JPS6369749A
Cited
JPS641430A
Cited
US4889834A
Cited
US5011799A
Cited
JPH03290355A
Cited
US5194073A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-02-14 | 1997-08-16 | 1998-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-14 | 2001-08-16 | 2002-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-14 | 2005-08-16 | 2006-02-15 | $7700.00 | Window Closed / Lapsed |